It’s showing up this summer (sometime)

Apple hasn’t changed its late summer delivery date since the company first previewed Mountain Lion in February, so it’s a good bet that the next Mac OS will be showing up sometime this summer. That said, “summer” can mean anytime from now until September 21, so don’t get your hopes up for Mountain Lion to be ready on Day One of WWDC.

It brings iOS closer to the Mac

No, you won’t be running your iOS apps on your Mac (at least, that we know of), but Mountain Lion is all about integration with Apple’s mobile operating system. Familiar applications like iCal, Address Book, and iChat have hopped aboard the iOS name-train and will go by Calendar, Contacts, and Messages, while iOS-only apps like Notes, Reminders, and Game Center will make their grand debut on the Mac.

It wants to keep you notified

iOS apps aren’t the only thing Apple’s mobile operating system has for Mountain Lion—the Mac OS will also receive iOS’s notifications system when it arrives later this summer. Notification Center on the Mac will keep track of your app updates, Messages, emails, calendar invites, and—perhaps—even third-party app alerts.

It sports some new looks

New names are fun; new features are better. There are a whole bunch of new system options present in Mountain Lion, like improvements to Dashboard and more Accessibility changes.

Your system apps will get a few nice features, too: Safari has a unified search bar and new share features; Mail sports inline find, notification settings, and VIPs; and Preview receives a major overhaul.

It’s trying to keep you safe(r)

In Lion, Apple’s big push toward security revolved around sandboxing Mac apps. With the Mac App Store officially sandboxed as of June 1, however, Apple’s next project is to make sure folks purchasing programs outside of the store can have confidence in their buys.

Gatekeeper is Apple’s proposed solution. It allows you to choose one of three settings for running applications on your computer: those only purchased from the App Store, those that have registered with Apple using Developer ID, or any application downloaded from any developer.

It’s the middle option—which lets developers code-sign their apps with Apple to ensure that there’s no malware at play—that may prove most popular when Mountain Lion launches; it allows many developers with apps that can’t abide by the Mac App Store’s sandboxing guidelines (Bare Bones Software’s BBEdit, for one) to still have their apps certified by Apple.

It still has things to come (probably)

Yes, we know a fair amount about this version of OS X, but there's still plenty to discover. As we mentioned earlier, Mountain Lion doesn't ship until the wonderfully-ambiguous "late summer," and for good reason: Knowing Apple, the company still wants to show off a few tricks that it’s taught this big cat—probably on-stage at WWDC. We'll have live coverage of the keynote and information on Mountain Lion as WWDC week progresses, so stay tuned. And if you're dying for more information than even this round-up can provide, check out our Mountain Lion FAQ.

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